1. Field of the Invention
This invention relates to functionalized carbon nanotubes and material containing functionalized carbon nanotubes suitable for use as electrodes and as electrode material in supercapacitors.
2. Discussion of the Related Art
It is well known in the art that carbon nanotubes can exhibit semiconducting or metallic behavior. Additional properties that make carbon nanotubes of interest are high surface area, high electrical conductivity, high thermal conductivity and stability, and good mechanical properties. See U.S. Patent Application Publication US 2003/0164427 A1.
Supercapacitors typically have specific capacitance of greater than 100 F/g, as opposed to conventional capacitors with specific capacitance on the order of only several F/g. Supercapacitors refer to, without limitation, electrochemical capacitors, electric double layer capacitors and ultracapacitors.
Capacitor electrodes prepared from carbon nanotube-containing materials can exhibit high levels of performance. However, for supercapacitor applications even higher levels of capacitance performance are desirable or required.
A need exists, therefore, for nanotube-containing materials for use in as electrodes in supercapacitors, or capacitors, exhibiting higher levels of capacitance.